CN116005263A - Crystal material and preparation method and application thereof - Google Patents

Abstract

The application discloses a crystal material, a preparation method and application thereof, and belongs to the field of optical materials. A crystalline material having a chemical formula of 4 (C ₃ N ₆ H ₆ )·HPF ₆ The method comprises the steps of carrying out a first treatment on the surface of the The crystal material contains pi conjugated construction units; the pi conjugated building block is (C) ₃ N ₆ ) ^3‑ The method comprises the steps of carrying out a first treatment on the surface of the The pi conjugated construction unit is perpendicular to the c axis; the pi conjugated building blocks are arranged in layers. The material shows that the crystal has larger double refractive index through first sexual principle calculation. A birefringence of 0.247 at 1042 nm; the birefringent crystal material has good transmittance in a broad spectrum range of 200 nm-2500 nm.

Description

Crystal material and preparation method and application thereof

Technical Field

The application relates to a crystal material, a preparation method and application thereof, and belongs to the field of optical materials.

Background

When one beam of light is irradiated on the crystal interface, two beams of refraction light are generated, and the phenomenon is called double refraction. The reason for the occurrence of the birefringence is that a crystal capable of generating such a phenomenon is called a birefringent crystal due to the anisotropy of the crystal material itself. Crystals that can produce birefringence can be classified into uniaxial crystals and biaxial crystals, and crystals of the trigonal, tetragonal or hexagonal systems are uniaxial crystals, and crystals of the orthorhombic, monoclinic and triclinic systems are called biaxial crystals. The application of the birefringent crystal in the optical field is very wide, such as photolithography, communication and micromachining.

The birefringence crystals that have been commercially used at present include rutile crystals, lithium niobate crystals, yttrium vanadate crystals, calcite crystals, silica crystals, magnesium fluoride crystals, and α -BaB ₂ O ₄ Crystals, and the like. The yttrium vanadate crystal is a crystal with excellent performance, but the ultraviolet cut-off edge is above 400nm, and the transmission capacity of the yttrium vanadate crystal is poor for the outside wave band below 400nm, so that the yttrium vanadate crystal cannot be applied to the ultraviolet deep ultraviolet wave band. The magnesium fluoride crystal has a longer transmission range (110 nm-8500 nm), is the only birefringent crystal capable of being used in the ultraviolet deep ultraviolet band, but has smaller birefringence, and seriously affects the application. Also plagued by the magnitude of the birefringence are silica crystals. And alpha-BaB ₂ O ₄ The crystal has a wider spectral transmission range (189-3500 nm), a shorter ultraviolet cut-off edge, a larger double refractive index (0.159@253.7 nm) and important application value in the ultraviolet region, but the crystal has phase change at high temperature, is extremely easy to crack in the growth process and is not easy to obtain large-size single crystals.

Along with the development of technology, the requirements of people on the birefringent crystal are higher and higher, and the finding of an excellent birefringent crystal is of great significance in terms of quality and quantity. Excellent birefringent crystals are required to be easy to process and grow, have large birefringent indexes and permeability, and have stable physical and chemical properties, so researchers have been continuously searching and trying in recent years to find an excellent birefringent crystal material and use the material in practical applications.

Disclosure of Invention

According to one aspect of the present application, a crystalline material is provided that exhibits a relatively high birefringence as calculated by first principles of nature. A birefringence of 0.24 at 1042nm7. The birefringent crystal material 4 (C ₃ N ₆ H ₆ )·HPF ₆ Has good transmittance in a broad spectrum range of 200nm to 2500 nm.

A crystalline material having a chemical formula of 4 (C ₃ N ₆ H ₆ )·HPF ₆ ；

The crystal material contains pi conjugated construction units;

the pi conjugated building block is (C) ₃ N ₆ ) ^3- ；

The pi conjugated construction unit is perpendicular to the c axis;

the pi conjugated building blocks are arranged in layers.

Alternatively, C ₃ N ₆ H ₆ The two are connected through hydrogen bonds of N-H.N in the molecule;

(PF ₆ ) ^- and C ₃ N ₆ H ₆ The three-dimensional structure is formed by intramolecular hydrogen bonding.

The crystal material contains pi conjugated building block (C) ₃ N ₆ ) ^3- And the pi conjugated building block is arranged in a layer form perpendicular to the c axis in the crystal structure, and the arrangement mode can induce formation of large conjugated pi bonds to form large double refractive indexes. The melamine is linked by intramolecular N-H.N hydrogen bonds, and (PF ₆ ) ^- And the three-dimensional structure is finally formed by linking with melamine through intramolecular hydrogen bonds.

Optionally, the crystalline material is of monocrystalline structure.

Optionally, the crystal material belongs to a trigonal system, and the space group is

Optionally, the unit cell parameters of the crystalline material are as follows:

α＝90°，β＝90°，γ＝120°。

alternatively, the crystalline material has a birefringence of 0.220 to 0.250 at 1042nm calculated by the first principle of refraction.

According to a second aspect of the present application, a method of preparing a crystalline material is provided.

The preparation method of the crystal material comprises the following steps:

the mixture containing melamine, hexafluorophosphate compound and water is regulated to be weak acid pH value, and the crystal material is obtained after the reaction;

the molar ratio of melamine to hexafluorophosphate compound was 4.5:1 to 5:1, a step of;

the mole volume ratio of melamine to water is 1mmol:5 mL-1 mmol:10mL.

Alternatively, the molar ratio of melamine to hexafluorophosphate compound is independently selected from 4.5: 1. 4.6: 1. 4.7: 1. 4.8: 1. 4.9: 1. 5:1 or a range value between any two.

Alternatively, the molar volume ratio of melamine to water is independently selected from 1mmol:5mL, 1mmol:6mL, 1mmol:7mL, 1mmol:8mL, 1mmol:9mL, 1mmol: any value in 10mL or a range of values between any two.

Alternatively, the hexafluorophosphate compound is selected from LiPF ₆ 、NaPF ₆ 、KPF ₆ 、CsPF ₆ 、HPF ₆ At least one of them.

Alternatively, the reaction conditions are as follows:

the temperature is 40-90 ℃;

the time is 30 min-60 min.

Alternatively, the temperature of the reaction is independently selected from any value or range of values between any two of 40 ℃, 42 ℃, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 80 ℃, 90 ℃.

Alternatively, the time of the reaction is independently selected from any value or range of values between any two of 30min, 35min, 40min, 45min, 50min, 55min, 60min.

According to a third aspect of the present application there is provided the use of a crystalline material.

The crystal material and/or the crystal material obtained by the preparation method are applied to the preparation of a polarization beam splitter prism or an optical element.

Optionally, the polarizing beam splitting prism is one of a gram prism, a wollaston prism, a rochon prism and a beam splitting polarizer;

the optical element is selected from one of an optical isolator, a circulator, a beam shifter, an optical polarizer, an optical modulator, an optical polarizer, a polarization beam splitter, a phase delay device and an electro-optical modulation device.

The beneficial effects that this application can produce include:

1) The crystal material provided by the application shows that the crystal has larger double refractive index through first principle calculation. A birefringence of 0.247 at 1042 nm; the birefringent crystal material 4 (C ₃ N ₆ H ₆ )·HPF ₆ Has good transmittance in a broad spectrum range of 200nm to 2500 nm.

Drawings

FIG. 1 shows the results of examples 1-3, 4 (C ₃ N ₆ H ₆ )·HPF ₆ A schematic diagram of the structure of the crystal.

FIG. 2 shows the results of examples 1-3, 4 (C ₃ N ₆ H ₆ )·HPF ₆ Crystalline birefringence spectrum.

Fig. 3 is a schematic view of a polarization beam splitter prism fabricated in example 4.

Detailed Description

The present application is described in detail below with reference to examples, but the present application is not limited to these examples.

Unless otherwise indicated, all starting materials in the examples of the present application were purchased commercially.

The analytical method in the examples of the present application is as follows:

the crystal structure data is tested by using a four-circle diffractometer of the model Synergy Custom system of Rigaku ROD, and the wavelength is Ga K alpha ray

Recording data at room temperature;

the birefringence data of the crystal is calculated by the first principle of nature. The parameters were calculated using Materials studio8.0 software and the settings were not further adjusted using default values.

Example 1

Preparation of 4 (C) by aqueous solution method ₃ N ₆ H ₆ )·HPF ₆ A method of birefringent crystal comprising the steps of:

1) 4.5mmol melamine, 1mmol sodium hexafluorophosphate are dissolved in a clean beaker containing 5mL water and the solution pH is adjusted to weak acidity;

2) The mixed aqueous solution is placed on a magnetic stirrer to be heated to 60 ℃ and is continuously stirred for 30min in the heating process. Then the crystal is cooled and crystallized at room temperature, and a large amount of colorless transparent single crystals appear after three or five days.

3) The crystal obtained in the step 2) is washed with purified water and then naturally dried, the sample obtained in the example 1 is placed on a quadric diffractometer to collect diffraction data, and the crystal structure obtained after the data is reduced and refined by software is shown in fig. 1. Containing two melamine rings and one HPF in its asymmetric unit ₆ 。

4) And 3) calculating the single crystal data obtained in the step 3) by using a first principle, wherein the calculation by using the first principle shows that the compound has larger double refractive index. The birefringence at 1024nm was 0.247.

Example 2

Preparation of 2 (C) by aqueous solution method ₃ N ₆ H ₆ )·HPF ₆ ·H ₂ A method of O-birefringent crystal comprising the steps of:

1) 4.8mmol melamine, 1mmol potassium hexafluorophosphate are dissolved in a clean beaker containing 8mL water and the solution pH is adjusted to weak acidity;

2) The mixed aqueous solution is placed on a magnetic stirrer to be heated to 50 ℃ and is continuously stirred for 40min in the heating process. Then the crystal is cooled and crystallized at room temperature, and a large amount of colorless transparent single crystals appear after three or five days.

3) The crystal obtained in the step 2) is washed with purified water and then naturally dried, the sample obtained in the example 2 is placed on a quadric diffractometer to collect diffraction data, and the crystal structure obtained after the data is reduced and refined by software is shown in fig. 1. Containing two melamine rings and one HPF in its asymmetric unit ₆ 。

4) And 3) calculating the single crystal data obtained in the step 3) by using a first principle, wherein the calculation by using the first principle shows that the compound has larger double refractive index. The birefringence at 1024nm was 0.247.

Example 3

Preparation of 4 (C) by aqueous solution method ₃ N ₆ H ₆ )·HPF ₆ A method of birefringent crystal comprising the steps of:

1) 5mmol of melamine, 1mmol of lithium hexafluorophosphate are dissolved in a clean beaker containing 10mL of water and the pH of the solution is adjusted to weak acidity;

2) The mixed aqueous solution is placed on a magnetic stirrer to be heated to 80 ℃ and is continuously stirred for 60min in the heating process. Then the crystal is cooled and crystallized at room temperature, and a large amount of colorless transparent single crystals appear after three or five days.

3) The crystal obtained in the step 2) is washed with purified water and then naturally dried, the sample obtained in the example 3 is placed on a quadric diffractometer to collect diffraction data, and the crystal structure obtained after the data is reduced and refined by software is shown in fig. 1. Containing two melamine rings and one HPF in its asymmetric unit ₆ 。

4) And 3) calculating the single crystal data obtained in the step 3) by using a first principle, wherein the calculation by using the first principle shows that the compound has larger double refractive index. The birefringence at 1024nm was 0.247.

Example 4 polarizing prism

Any of 4 (C) obtained in examples 1-3 ₃ N ₆ H ₆ )·HPF ₆ Crystals, which are bonded together after processing to produce a polarizing prism as shown in FIG. 3, and when a light beam is perpendicularly incident on the prism face, the light beam is reflected in the prism 1Neither o nor e light is deflected; light is totally reflected at the glue face o and totally absorbed by the absorbing coating on the prism face, while light e exits from the second prism.

The foregoing description is only a few examples of the present application and is not intended to limit the present application in any way, and although the present application is disclosed in the preferred examples, it is not intended to limit the present application, and any person skilled in the art may make some changes or modifications to the disclosed technology without departing from the scope of the technical solution of the present application, and the technical solution is equivalent to the equivalent embodiments.

Claims (10)

1. A crystalline material characterized in that the crystalline material has a chemical formula of 4 (C ₃ N ₆ H ₆ )·HPF ₆ ；

The crystal material contains pi conjugated construction units;

the pi conjugated building block is (C) ₃ N ₆ ) ^3- ；

The pi conjugated construction unit is perpendicular to the c axis;

the pi conjugated building blocks are arranged in layers.

2. The crystalline material of claim 1, wherein C ₃ N ₆ H ₆ The two are connected through hydrogen bonds of N-H.N in the molecule;

(PF ₆ ) ^- and C ₃ N ₆ H ₆ The three-dimensional structure is formed by intramolecular hydrogen bonding.

3. The crystalline material of claim 1, wherein the crystalline material is a single crystal structure.

4. The crystalline material of claim 1, wherein the crystalline material is in a trigonal system and the space group is

Preferably, the unit cell parameters of the crystalline material are as follows:

α＝90°，β＝90°，γ＝120°。

5. the crystalline material of claim 1, having a birefringence calculated by first principles of refraction at 1042nm of from 0.220 to 0.250.

6. The method for producing a crystalline material according to any one of claims 1 to 5, comprising the steps of:

the mixture containing melamine, hexafluorophosphate compound and water is regulated to be weak acid pH value, and the crystal material is obtained after the reaction;

the molar ratio of melamine to hexafluorophosphate compound was 4.5:1 to 5:1, a step of;

the mole volume ratio of melamine to water is 1mmol:5 mL-1 mmol:10mL.

7. The method of claim 6, wherein the hexafluorophosphate compound is selected from LiPF ₆ 、NaPF ₆ 、KPF ₆ 、CsPF ₆ 、HPF ₆ At least one of them.

8. The method according to claim 6, wherein the reaction conditions are as follows:

the temperature is 40-90 ℃;

the time is 30 min-60 min.

9. Use of a crystalline material according to any one of claims 1 to 5 and/or a crystalline material obtained by a method of preparation according to any one of claims 6 to 8 for the preparation of a polarizing beam splitter prism or an optical element.

10. The use according to claim 9, wherein the polarizing beam splitting prism is selected from one of a gram prism, a wollaston prism, a rochon prism, a beam splitting polarizer;

the optical element is selected from one of an optical isolator, a circulator, a beam shifter, an optical polarizer, an optical modulator, an optical polarizer, a polarization beam splitter, a phase delay device and an electro-optical modulation device.

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